[java/en] Update java.html.markdown with modern Java updates (#5128)

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Mayuresh Kumbhar 2024-09-29 04:29:02 +02:00 committed by GitHub
parent 495272cff9
commit 742574706b
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@ -44,6 +44,9 @@ Multi-line comments look like this.
import java.util.ArrayList;
// Import all classes inside of java.security package
import java.security.*;
// Java to illustrate calling of static members and methods without calling classname
import static java.lang.Math.*;
import static java.lang.System.*;
public class LearnJava {
@ -211,9 +214,21 @@ public class LearnJava {
// Prefer the String constructor when you need an exact value.
BigDecimal tenCents = new BigDecimal("0.1");
// Type inference with 'var'
var x = 100; // int
var y = 1.90; // double
var z = 'a'; // char
var p = "tanu"; // String
var q = false; // boolean
// Strings
String fooString = "My String Is Here!";
// Text blocks
vat textBlock = """
This is a <Text Block> in Java
""";
// \n is an escaped character that starts a new line
String barString = "Printing on a new line?\nNo Problem!";
// \t is an escaped character that adds a tab character
@ -459,6 +474,8 @@ public class LearnJava {
System.out.println(br.readLine());
// In Java 7, the resource will always be closed, even if it throws
// an Exception.
} catch (IOException | SQLException ex) {
// Java 7+ Multi catch block handle both exceptions
} catch (Exception ex) {
//The resource will be closed before the catch statement executes.
System.out.println("readLine() failed.");
@ -852,6 +869,12 @@ public abstract class Mammal()
}
}
// Java Records are a concise way to define immutable data carrier classes, automatically
// generating boilerplate code like constructors, equals(), hashCode()and toString().
// This automatically creates an immutable class Person with fields name and age.
public record Person(String name, int age) {}
Person p = new Person("Alice", 30);
// Enum Type
//
// An enum type is a special data type that enables for a variable to be a set